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Is "having a baby without a fart eye" a curse come true?
After the birth of the child, the midwife will check the newborn's physical condition according to the procedure to see if the child's body organs are intact and deformed, but suddenly find that some children are born without anus.
atresia, Source: Literature[1]
There is a folk saying that there will be no children in the absence of virtue to do more offspring, which is actually groundless, and medically call this newborn defect atresia, which is a clinical manifestation of congenital rectal development deformity.
First, this is a common digestive tract deformity
Congenital rectal development deformity is actually a common neonatal defect disease, the incidence rate in newborns is 1:5000-1:1500, accounting for the first place of gastrointestinal malformations, generally male babies are more than female babies.
In addition to genetic factors, prenatal exposure of parents to nicotine, alcohol, caffeine, illicit drugs, occupational hazards, overweight, obesity and diabetes is also a contributing factor. Because there is no anus, the fetal stool in the baby's stomach cannot be discharged, which can easily cause complications such as intestinal perforation, intestinal obstruction, peritonitis, and even lead to death.
▌So how does this deformity come about?
In the early embryonic stage, the baby's anus and rectum have not yet separated, forming a cloaca along with the bladder. When the embryo develops to about the fourth week, the cloaca begins to separate different functional organs, the dorsal part forms the rectum, the ventral part is the urinary reproductive sinus, and the urinary rectum is in between, and wait until the eighth week of the embryo to form a normal rectum and canal.
If the membrane is not broken or the canal is abnormally developed, the rectum cannot communicate with the outside world, forming a simple rectal atresia. If, during this period, the cloatropharic septum is underdeveloped and the rectum is not completely separated from the urinary-genitourinary sinuses, it leads to the formation of various fistulas (pathological drainage ducts between two luminal organs) between the rectum and the urogenital line.
Source: Histology and Embryology (People's Medical Publishing House, 2007)
In general, almost all of the people with bladder fistulas are boys, and the rectal fistulas in girls are mostly vaginal fistulas. At this time, although the child can defecate through the vagina or urethra, the feces remain in the urethra or vagina, which is easy to cause cystitis, pyelonephritis, vaginitis and so on.
According to the clinical characteristics, we can divide congenital rectal developmental malformations into the following categories:
Table 1. Classification of congenital rectal developmental malformations
About 40% of cases of congenital rectal malformations are accompanied by other organ developmental malformations, including the genitourinary system (21% to 61% and above), spine and spinal cord (5% to 40%), the rest of the gastrointestinal tract (10% to 25%), and the heart (9% to 20%). In particular, concomitant malformations of the urinary system are more common, and a careful systemic examination should be done before surgery.
Second, abnormal bowel movements are the most important symptoms
Children with congenital dysplasia of the rectum can first be judged by appearance, and the child may be found to have no anus or abnormal position, or a narrow external mouth. Secondly, it can also be combined with the clinical manifestations of the child, mainly including abnormalities of the digestive system.
Patients with complete atresia of the anus have acute obstruction after birth, vomiting, vomit containing bile or meconium-like substances, and no defecation for 24 hours after birth.
If the person is a rectal stenosis or other fistula, there will be difficulty defecation, thin stools, bloating in the weeks, months, or years after birth, and large clumps of fecal mass may be palpable in the left lower quadrant, followed by chronic intestinal obstruction.
Exhaustion and feces from the urethral orifice are the main symptoms of rectal urinary fistula. Among them, the bladder fistula is mixed with urine due to meconium entering the bladder, and the child has green urine in the process of urination, but only a small amount of meconium is excreted at the beginning of urination, and then meconium is not mixed with urine, and the urine is transparent. Increased meconium and gas excretion may be seen when the child urinates, and when not urinating, there is no gas excretion due to the control of the bladder sphincter.
The following adjunctive tests may also be used to help confirm the diagnosis:
1. Slowly insert along the posterior wall of the urethra with the smallest metal urinary catheter or probe, enter the rectum through the fistula, touch the anus with your fingers to reach the tip of the probe, roughly determine the shape, length and width of the fistula, and roughly calculate the distance between the rectal cecum and the skin.
2. X-ray can be diagnosed as rectal bladder fistula when x-ray shows a gas or fluid level in the bladder. Rectal stenosis is a rare malformation, and fistula angiography can be definitively diagnosed.
3. Surgical reconstruction of the anus
development deformity is mainly treated surgically, when the child is diagnosed, it is necessary to determine the location of the rectal end of the child with congenital rectal development deformity according to imaging examination, and combine the experience of the surgeon and the child's state and existing conditions to decide as soon as possible whether to proceed with colostomy or direct radical resection.
Among them, patients with middle and high-grade congenital rectal development deformities need to have a colostomy first if they do not have a stage of surgery conditions, which is colloquially speaking, to reopen the upper intestine from the belly, pull it out, and create a new excretory opening.
atresia and postoperative photographs (larger rectal urethral prostate fistulas found and closed intraoperatively), Source: Literature[2]
The choice of colostomy position and method is crucial, and the choice of ostomy orifice should be satisfied: the ostomy orifice is not easy to come out or retract, which is conducive to pre-radical angiography and cleaning of the distal intestinal tube, and does not hinder the dragging out of the distal intestinal tube of radical resection. Therefore, clinical choice is often descending colon or sigmoid colon initiation ostomy, sigmoid colon initiation because there is no posterior peritoneum binding, easy to operate, more and more popular.
In addition, different radical surgical methods are used according to their type and the height of the rectal end: there are mainly rectal stenosis and dilation, membrane atresia incision, perineal plasty and rectal fistula displacement plasty.
The treatment effect of congenital anorectal malformations has improved significantly in recent years, with the total case fatality rate falling from 25%-30% in the past to about 10% in recent years, and the surgical mortality rate has dropped to about 2%. However, about one-third of cases still have some degree of dysfunction after surgery, resulting in abnormal bowel movements.
In addition, the higher the location of anorectal malformations, the higher the incidence and severity of postoperative defecation dysfunction. The incidence of postoperative bowel disorders was 86.4% of patients with high dysfunction, 47.9% of median malformations, and 27% of low deformities. Severe dysfunction can cause long-term, even lifelong pain and annoyance to children and their families, so in addition to reasonable treatment, it is also important to adhere to postoperative expansion and defecation training.
bibliography:
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This article was first published: Pediatrics Channel of the Medical Professions
This article is written by Stey Tsai
Editor-in-Charge: CiCi